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Dabsan S, Twito G, Biadsy S, Igbaria A. Less is better: various means to reduce protein load in the endoplasmic reticulum. FEBS J 2024. [PMID: 38865586 DOI: 10.1111/febs.17201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 04/08/2024] [Accepted: 06/05/2024] [Indexed: 06/14/2024]
Abstract
The endoplasmic reticulum (ER) is an important organelle that controls the intracellular and extracellular environments. The ER is responsible for folding almost one-third of the total protein population in the eukaryotic cell. Disruption of ER-protein folding is associated with numerous human diseases, including metabolic disorders, neurodegenerative diseases, and cancer. During ER perturbations, the cells deploy various mechanisms to increase the ER-folding capacity and reduce ER-protein load by minimizing the number of substrates entering the ER to regain homeostasis. These mechanisms include signaling pathways, degradation mechanisms, and other processes that mediate the reflux of ER content to the cytosol. In this review, we will discuss the recent discoveries of five different ER quality control mechanisms, including the unfolded protein response (UPR), ER-associated-degradation (ERAD), pre-emptive quality control, ER-phagy and ER to cytosol signaling (ERCYS). We will discuss the roles of these processes in decreasing ER-protein load and inter-mechanism crosstalk.
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Affiliation(s)
- Salam Dabsan
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Gal Twito
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Suma Biadsy
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Aeid Igbaria
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
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2
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Florance I, Ramasubbu S. Regulation of genes involved in the metabolic adaptation of murine microglial cells in response to elevated HIF-1α mediated activation. Immunogenetics 2024; 76:93-108. [PMID: 38326657 DOI: 10.1007/s00251-024-01334-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 01/15/2024] [Indexed: 02/09/2024]
Abstract
Microglia cells are activated in response to different stress signals. Several metabolic adaptations underlie microglia activation in the brain. Among these, in conditions like ischemic stroke and, hypoxic stress stimuli activate microglia cells. Hypoxic stress is mediated by HIF-1α. Although HIF-1α has been implicated in the alteration of metabolic pathways, changes in microglia lipid metabolism during M1 activation of microglia induced by elevated HIF-1α levels are yet to be understood. This can also merit interest in the development of novel targets to mitigate chronic inflammation. Our study aims to elucidate the transcriptional regulation of metabolic pathways in microglia cells during HIF-1α mediated activation. To study the adaptations in the metabolic pathways we induced microglia activation, by activating HIF-1α. Here, we show that microglia cells activated in response to elevated HIF-1α require ongoing lipogenesis and fatty acid breakdown. Notably, autophagy is activated during the initial stages of microglia activation. Inhibition of autophagy in activated microglia affects their viability and phagocytic activity. Collectively, our study expands the understanding of the molecular link between autophagy, lipid metabolism, and inflammation during HIF-1α mediated microglial activation that can lead to the development of promising strategies for controlling maladaptive activation states of microglia responsible for neuroinflammation. Together, our findings suggest that the role of HIF-1α in regulating metabolic pathways during hypoxia in microglia is beyond optimization of glucose utilization and distinctly regulates lipid metabolism during pro-inflammatory activation.
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Affiliation(s)
- Ida Florance
- Center for Nanobiotechnology, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India
| | - Seenivasan Ramasubbu
- Center for Nanobiotechnology, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India.
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3
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Oh SJ, Park K, Sonn SK, Oh GT, Lee MS. Pancreatic β-cell mitophagy as an adaptive response to metabolic stress and the underlying mechanism that involves lysosomal Ca 2+ release. Exp Mol Med 2023; 55:1922-1932. [PMID: 37653033 PMCID: PMC10545665 DOI: 10.1038/s12276-023-01055-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/18/2023] [Accepted: 05/11/2023] [Indexed: 09/02/2023] Open
Abstract
Mitophagy is an excellent example of selective autophagy that eliminates damaged or dysfunctional mitochondria, and it is crucial for the maintenance of mitochondrial integrity and function. The critical roles of autophagy in pancreatic β-cell structure and function have been clearly shown. Furthermore, morphological abnormalities and decreased function of mitochondria have been observed in autophagy-deficient β-cells, suggesting the importance of β-cell mitophagy. However, the role of authentic mitophagy in β-cell function has not been clearly demonstrated, as mice with pancreatic β-cell-specific disruption of Parkin, one of the most important players in mitophagy, did not exhibit apparent abnormalities in β-cell function or glucose homeostasis. Instead, the role of mitophagy in pancreatic β-cells has been investigated using β-cell-specific Tfeb-knockout mice (TfebΔβ-cell mice); Tfeb is a master regulator of lysosomal biogenesis or autophagy gene expression and participates in mitophagy. TfebΔβ-cell mice were unable to adaptively increase mitophagy or mitochondrial complex activity in response to high-fat diet (HFD)-induced metabolic stress. Consequently, TfebΔβ-cell mice exhibited impaired β-cell responses and further exacerbated metabolic deterioration after HFD feeding. TFEB was activated by mitochondrial or metabolic stress-induced lysosomal Ca2+ release, which led to calcineurin activation and mitophagy. After lysosomal Ca2+ release, depleted lysosomal Ca2+ stores were replenished by ER Ca2+ through ER→lysosomal Ca2+ refilling, which supplemented the low lysosomal Ca2+ capacity. The importance of mitophagy in β-cell function was also demonstrated in mice that developed β-cell dysfunction and glucose intolerance after treatment with a calcineurin inhibitor that hampered TFEB activation and mitophagy.
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Affiliation(s)
- Soo-Jin Oh
- Soonchunhyang Institute of Medi-bio Science and Division of Endocrinology, Department of Internal Medicine, Soonchunhyang University College of Medicine, Cheonan, 31151, Korea
| | - Kihyoun Park
- Soonchunhyang Institute of Medi-bio Science and Division of Endocrinology, Department of Internal Medicine, Soonchunhyang University College of Medicine, Cheonan, 31151, Korea
| | - Seong Keun Sonn
- Heart-Immune-Brain Network Research Center, Department of Life Science, Ewha Womans University, Seoul, 03767, Korea
| | - Goo Taeg Oh
- Heart-Immune-Brain Network Research Center, Department of Life Science, Ewha Womans University, Seoul, 03767, Korea
| | - Myung-Shik Lee
- Soonchunhyang Institute of Medi-bio Science and Division of Endocrinology, Department of Internal Medicine, Soonchunhyang University College of Medicine, Cheonan, 31151, Korea.
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4
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Liu S, Fang X, Zhu R, Zhang J, Wang H, Lei J, Wang C, Wang L, Zhan L. Role of endoplasmic reticulum autophagy in acute lung injury. Front Immunol 2023; 14:1152336. [PMID: 37266445 PMCID: PMC10231642 DOI: 10.3389/fimmu.2023.1152336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 05/03/2023] [Indexed: 06/03/2023] Open
Abstract
Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), the prime causes of morbidity and mortality in critically ill patients, are usually treated by general supportive treatments. Endoplasmic reticulum autophagy (ER-phagy) maintains cellular homeostasis by degrading damaged endoplasmic reticulum (ER) fragments and misfolded proteins. ER-phagy is crucial for maintaining ER homeostasis and improving the internal environment. ER-phagy has a particular role in some aspects, such as immunity, inflammation, cell death, pathogen infection, and collagen quality. In this review, we summarized the definition, epidemiology, and pathophysiology of ALI/ARDS and described the regulatory mechanisms and functions of ER-phagy as well as discussed the potential role of ER-phagy in ALI/ARDS from the perspectives of immunity, inflammation, apoptosis, pathogen infection, and fibrosis to provide a novel and effective target for improving the prognosis of ALI/ARDS.
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Affiliation(s)
- Shiping Liu
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, China
| | - Xiaoyu Fang
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, China
| | - Ruiyao Zhu
- Department of Infection Prevention and Control, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jing Zhang
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, China
| | - Huijuan Wang
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jiaxi Lei
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, China
| | - Chaoqun Wang
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Lu Wang
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, China
| | - Liying Zhan
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, China
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Deng H, Chen W, Zhang B, Zhang Y, Han L, Zhang Q, Yao S, Wang H, Shen XL. Excessive ER-phagy contributes to ochratoxin A-induced apoptosis. Food Chem Toxicol 2023; 176:113793. [PMID: 37080527 DOI: 10.1016/j.fct.2023.113793] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/17/2023] [Accepted: 04/17/2023] [Indexed: 04/22/2023]
Abstract
The nephrotoxic secondary fungal metabolite ochratoxin A (OTA) is ubiquitously existed in foodstuffs and feeds. Although our earlier research provided preliminary evidence that endoplasmic reticulum (ER) was crucial in OTA-induced nephrotoxicity, more research is necessary to understand the fine-tune mechanisms involving ER stress (ERS), ER-phagy, and apoptosis. In the present study, the cell viability and protein expressions of human proximal tubule epithelial (HK-2) cells in response to OTA and/or chloroquine/rapamycin/sodium phenylbutyrate/tunicamycin were determined via cell viability assay, apoptosis analysis, and Western blot analysis. The findings showed that a 24 h-treatment of 0.25-4 μM OTA could significantly reduced the cell viability (P < 0.05), which notably increased with the addition of chloroquine and sodium phenylbutyrate, while decreased with the addition of rapamycin and tunicamycin as compared to group OTA (P < 0.05). A 24 h-treatment of 1-4 μM OTA could markedly induce apoptosis via increasing the protein expressions of GRP78, p-eIF2α, Chop, LC3B-II, Bak, and Bax, and inhibiting the protein expressions of DDRGK1, UBA5, Lonp1, Tex264, FAM134B, p-mTOR, p62, and Bcl-2 in HK-2 cells (P < 0.05). In conclusion, OTA activated ERS, unfolded protein response, and subsequent excessive ER-phagy, thus inducing apoptosis, and the vicious cycle between excessive ER-phagy and ERS could further promote apoptosis in vitro.
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Affiliation(s)
- Huiqiong Deng
- School of Public Health, Zunyi Medical University, Zunyi, 563000, Guizhou, PR China
| | - Wenying Chen
- School of Public Health, Zunyi Medical University, Zunyi, 563000, Guizhou, PR China
| | - Boyang Zhang
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, 100083, PR China
| | - Yiwen Zhang
- School of Public Health, Zunyi Medical University, Zunyi, 563000, Guizhou, PR China
| | - Lingyun Han
- School of Public Health, Zunyi Medical University, Zunyi, 563000, Guizhou, PR China
| | - Qipeng Zhang
- School of Public Health, Zunyi Medical University, Zunyi, 563000, Guizhou, PR China; Depatment of Hospital Infection Control, The Affiliated Hospital of Zunyi Medical University, Zunyi, 563000, Guizhou, PR China
| | - Song Yao
- School of Public Health, Zunyi Medical University, Zunyi, 563000, Guizhou, PR China
| | - Hongwei Wang
- School of Public Health, Zunyi Medical University, Zunyi, 563000, Guizhou, PR China
| | - Xiao Li Shen
- School of Public Health, Zunyi Medical University, Zunyi, 563000, Guizhou, PR China.
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Huang Q, Chen S, Xiong X, Yin T, Zhang Y, Zeng G, Huang Q. Asprosin Exacerbates Endothelium Inflammation Induced by Hyperlipidemia Through Activating IKKβ-NF-κBp65 Pathway. Inflammation 2023; 46:623-638. [PMID: 36401667 DOI: 10.1007/s10753-022-01761-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 10/16/2022] [Accepted: 10/17/2022] [Indexed: 11/21/2022]
Abstract
Vascular endothelium dysfunction caused by endothelium inflammation is a trigger of numerous cardiovascular diseases. Vascular endothelium inflammation often occurs in patients with obesity. Asprosin (ASP) derived from white adipose tissue plays important roles in maintaining glucose homeostasis. However, effect of ASP on the vascular endothelium inflammation induced by hyperlipidemia and its underlying mechanism remains largely unclear. In this study, models of vascular endothelium inflammation were established to investigate the effect of ASP on the endothelium inflammation both in vivo and in vitro. Our data in vivo showed that recombinant ASP or high-fat diet (HFD) significantly increased the circulating levels of IL-6 and TNF-α and enhanced the adhesion of macrophages to endothelia characterized by the expression increase of CD68, ICAM-1, and VCAM-1 in rats. However, neutralization of ASP with an ASP specific antibody (AASP) significantly antagonized the changes induced by HFD. Similarly, our data in vitro also showed that ASP treatment elevated the expressions of IL-6, TNF-α, and ICAM-1 as well as VCAM-1. More important, our data revealed that the pro-inflammation effect of ASP was achieved by activating the IKKβ-NF-κBp65 pathway other than the oxidative stress pathway both in vivo and in vitro. In conclusion, our results demonstrate that ASP is a pro-inflammation player in the obesity-associated endothelium dysfunction. The findings would provide a novel target for the prevention and treatment of obesity-related cardiovascular diseases.
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Affiliation(s)
- Qianqian Huang
- Provincial Key Laboratory of Basic Pharmacology, Nanchang University, 461 Ba-Yi Street, Nanchang, Jiangxi, 330006, People's Republic of China
- Department of Pharmacology, School of Pharmacy, Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Sheng Chen
- Provincial Key Laboratory of Basic Pharmacology, Nanchang University, 461 Ba-Yi Street, Nanchang, Jiangxi, 330006, People's Republic of China
- Department of Pharmacology, School of Pharmacy, Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Xiaowei Xiong
- Provincial Key Laboratory of Basic Pharmacology, Nanchang University, 461 Ba-Yi Street, Nanchang, Jiangxi, 330006, People's Republic of China
- Department of Pharmacology, School of Pharmacy, Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Tingting Yin
- Provincial Key Laboratory of Basic Pharmacology, Nanchang University, 461 Ba-Yi Street, Nanchang, Jiangxi, 330006, People's Republic of China
- Department of Pharmacology, School of Pharmacy, Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Yanan Zhang
- Provincial Key Laboratory of Basic Pharmacology, Nanchang University, 461 Ba-Yi Street, Nanchang, Jiangxi, 330006, People's Republic of China
- Department of Pharmacology, School of Pharmacy, Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China
| | - Guohua Zeng
- Provincial Key Laboratory of Basic Pharmacology, Nanchang University, 461 Ba-Yi Street, Nanchang, Jiangxi, 330006, People's Republic of China.
- Department of Pharmacology, School of Pharmacy, Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China.
| | - Qiren Huang
- Provincial Key Laboratory of Basic Pharmacology, Nanchang University, 461 Ba-Yi Street, Nanchang, Jiangxi, 330006, People's Republic of China.
- Department of Pharmacology, School of Pharmacy, Nanchang University, Nanchang, Jiangxi, 330006, People's Republic of China.
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Li H, Jing Y, Qu X, Yang J, Pan P, Liu X, Gao H, Pei X, Zhang C, Yang Y. The Activation of Reticulophagy by ER Stress through the ATF4-MAP1LC3A-CCPG1 Pathway in Ovarian Granulosa Cells Is Linked to Apoptosis and Necroptosis. Int J Mol Sci 2023; 24:ijms24032749. [PMID: 36769070 PMCID: PMC9917250 DOI: 10.3390/ijms24032749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/16/2023] [Accepted: 01/26/2023] [Indexed: 02/04/2023] Open
Abstract
Female infertility is caused by premature ovarian failure (POF), which is triggered by the endoplasmic reticulum (ER) stress-mediated apoptosis of granulosa cells. The ER unfolded protein response (UPRer) is initiated to promote cell survival by alleviating excessive ER stress, but cellular apoptosis is induced by persistent or strong ER stress. Recent studies have reported that reticulophagy is initiated by ER stress. Whether reticulophagy is activated in the ER stress-mediated apoptosis of granulosa cells and which pathway is initiated to activate reticulophagy during the apoptosis of granulosa cells are unknown. Therefore, the role of reticulophagy in granulosa cell death and the relationship between ER stress and reticulophagy were investigated in this work. Our results suggest that the ER stress inducer tunicamycin causes POF in mice, which is attributed to the apoptosis of granulosa cells and is accompanied by the activation of UPRer and reticulophagy. Furthermore, granulosa cells were treated with tunicamycin, and granulosa cell apoptosis was triggered and increased the expression of UPRer and reticulophagy molecules. The expression of ATF4 was then downregulated by RNAi, which decreased the levels of autophagy and the reticulophagy receptor CCGP1. Furthermore, ATF4 targets MAP1LC3A, as revealed by the ChIP sequencing results, and co-IP results demonstrated that MAP1LC3A interacts with CCPG1. Therefore, reticulophagy was activated by ER stress through the ATF4-MAP1LC3A-CCPG1 pathway to mitigate ER stress. Additionally, the role of reticulophagy in granulosa cells was investigated by the knockdown of CCPG1 with RNAi. Interestingly, only a small number of granulosa cells died by apoptosis, whereas the death of most granulosa cells occurred by necroptosis triggered by STAT1 and STAT3 to impair ER proteostasis and the ER protein quality control system UPRer. Taken together, the results indicate that the necroptosis of granulosa cells is triggered by up- and downregulating the reticulophagy receptor CCPG1 through STAT1/STAT3-(p)RIPK1-(p)RIPK3-(p)MLKL and that reticulophagy is activated by ER stress through the ATF4-MAP1LC3A-CCPG1 pathway.
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Affiliation(s)
- Huiduo Li
- Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Key Laboratory of Reproduction and Genetics in Ningxia, Department of Histology and Embryology of Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
| | - Yanan Jing
- Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Key Laboratory of Reproduction and Genetics in Ningxia, Department of Histology and Embryology of Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
| | - Xiaoya Qu
- Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Key Laboratory of Reproduction and Genetics in Ningxia, Department of Histology and Embryology of Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
| | - Jinyi Yang
- Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Key Laboratory of Reproduction and Genetics in Ningxia, Department of Histology and Embryology of Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
| | - Pengge Pan
- Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Key Laboratory of Reproduction and Genetics in Ningxia, Department of Histology and Embryology of Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
| | - Xinrui Liu
- Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Key Laboratory of Reproduction and Genetics in Ningxia, Department of Histology and Embryology of Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
| | - Hui Gao
- Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Key Laboratory of Reproduction and Genetics in Ningxia, Department of Histology and Embryology of Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
| | - Xiuying Pei
- Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Key Laboratory of Reproduction and Genetics in Ningxia, Department of Histology and Embryology of Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
| | - Cheng Zhang
- College of Life Science, Capital Normal University, Beijing 100048, China
- Correspondence: or (C.Z.); or (Y.Y.); Tel.: +86-951-6980172 (Y.Y.)
| | - Yanzhou Yang
- Key Laboratory of Fertility Preservation and Maintenance, Ministry of Education, Key Laboratory of Reproduction and Genetics in Ningxia, Department of Histology and Embryology of Basic Medical College, Ningxia Medical University, Yinchuan 750004, China
- Correspondence: or (C.Z.); or (Y.Y.); Tel.: +86-951-6980172 (Y.Y.)
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Fernandes V, Preeti K, Sood A, Nair KP, Khan S, Rao BSS, Khatri DK, Singh SB. Neuroepigenetic Changes in DNA Methylation Affecting Diabetes-Induced Cognitive Impairment. Cell Mol Neurobiol 2022:10.1007/s10571-022-01278-5. [PMID: 36138280 DOI: 10.1007/s10571-022-01278-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 08/22/2022] [Indexed: 11/25/2022]
Abstract
Chronic diabetic conditions have been associated with certain cerebral complications, that include neurobehavioral dysfunctional patterns and morphological alterations of neurons, especially the hippocampus. Neuroanatomical studies done by the authors have shown decreased total dendritic length, intersections, dendritic length per branch order and nodes in the CA1 hippocampal region of the diabetic brain as compared to its normal control group, indicating reduced dendritic arborization of the hippocampal CA1 neurons. Epigenetic alterations in the brain are well known to affect age-associated disorders, however its association with the evolving diabetes-induced damage in the brain is still not fully understood. DNA hypermethylation within the neurons, tend to silent the gene expression of several regulatory proteins. The findings in the study have shown an increase in global DNA methylation in palmitic acid-induced lipotoxic Neuro-2a cells as well as within the diabetic mice brain. Inhibiting DNA methylation, restored the levels of HSF1 and certain HSPs, suggesting plausible effect of DNMTs in maintaining the proteostasis and synaptic fidelity. Neuroinflammation, as exhibited by the astrocyte activation (GFAP), were further significantly decreased in the 5-azadeoxycytidine group (DNMT inhibitor). This was further evidenced by decrease in proinflammatory cytokines TNF⍺, IL-6, and mediators iNOS and Phospho-NFkB. Our results suggest that changes in DNA methylation advocate epigenetic dysregulation and its involvement in disrupting the synaptic exactitude in the hippocampus of diabetic mice model, providing an insight into the pathophysiology of diabetes-induced neuroepigenetic changes.
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Affiliation(s)
- Valencia Fernandes
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, Telangana, 500037, India
| | - Kumari Preeti
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, Telangana, 500037, India
| | - Anika Sood
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, Telangana, 500037, India
| | - Kala P Nair
- Department of Neurophysiology, National Institute of Mental Health and Neuroscience (NIMHANS), Bengaluru, Karnataka, 560029, India
| | - Sabiya Khan
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, Telangana, 500037, India
| | - B S Shankaranarayana Rao
- Department of Neurophysiology, National Institute of Mental Health and Neuroscience (NIMHANS), Bengaluru, Karnataka, 560029, India
| | - Dharmendra Kumar Khatri
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, Telangana, 500037, India.
| | - Shashi Bala Singh
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, Telangana, 500037, India.
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